Integrated circuit production involves facilities that are expensive to build and maintain. Thus, it is common that integrated circuit production is performed at a foundry, which is specialized in production of integrated circuits, whereas design of the integrated circuits may be performed separately by a design house. The design house provides a design of the integrated circuit to the foundry, which then produces the integrated circuit.
The preparation of production process for an integrated circuit is a tedious task. Optical proximity correction (OPC) is performed at the foundry to ensure that the integrated circuit to be produced closely resembles the design. Then, hotspot analysis can be made to identify areas of the design in which lithographic printing errors are likely to be produced.
Based on failure of the hotspot analysis, OPC may be updated before another hotspot analysis is performed. Once a hotspot analysis is passed, a production test may be made and wafer verification may be performed to ensure that yield of the integrated circuit production is acceptable. Here, yield related design errors may be discovered. Thus, it may take a substantial amount of time (e.g., 4 months or more) and resources to discover design errors before an indication may be given to the design house that a re-design is required.
Attempts have been made at improving detection of lithographic hotspots using machine learning. In US 2015/0213374, a mechanism for detecting lithographic hotspots is disclosed. This mechanism utilizes extracted features on a set of training samples to train a machine learning classifier model. The machine learning may then use a set of known hotspots to train a machine learning model and uses the model to detect hotspots. Thus, in order to train the machine learning model, sets of known hotspots are required.
The use of machine learning for hotspot detection only detects errors based on hotspots and needs to include training based on known hotspots. Thus, the aid in designing of the integrated circuit still needs to be based on interaction with a foundry. Thus, it may still take substantial time before, e.g., yield errors for other reasons than hotspots are discovered, and a designer may not get input on a quality of the design without interaction with the foundry.
It would be desired to enable analysis of a design at the design house in order to improve quality of designs produced by the design house and without requiring interaction with a foundry (which may be time-consuming).